Mineral concentration



Patented Aug. 30, 1932 UNITED STATES PATENT OFFICE nnm'nnm'oan B. mar-m, or ROSELLE, maw ASSIGNOB r AIEBICAJT crutmm come, 02 new wax, u. 1, a comm-non or mum IINERAL CONCENTRATION R0 Drawing.

This invention relates to the treatment of ores, and more particularly has reference to mineral collecting agents and the separation and concentration of valuable constituents 6 from ores, and like bodies containing more than one mineral, by a floation process.

Heretofore separation and concentration of valuable mineral constituents from ores by various methods have been carried out. All

10 of those methods are more or less expensive,

resulting in relatively high costs of production, especially when the ore treated is poor in the constituent sought.

One particular method heretofore em- 1 ployed has comprised the steps of grinding the ore to fine particles, and then subjecting the mass to a flotation process in which there is employed a frothing agent, such as pine oil or other substances capable of producing a froth.

Some organic compounds, particularly certain alkyl thiocarbonates, when introduced into a flotation process materially increase the efliciency thereof, resulting in a greater yield of the desired constituents under the same operatingconditions or by accomplishing the same'results with a smaller amount of material. a

In spite of the remarkable properties of 39 the alkyl thiocarbonates heretofore used, and the increased efliciency afforded by their use, flotation processes are not carried out in as efficient and economical a manner as is desirable and possible to attain.

An object of this invention is to devise a method of treating ores and like bodies to efiect a separation and concentration oftheir valuable constituents that is more eflicient than any other method'heretofore practiced.

With this and other objects in View which may be incident to my improvements, the invention in general comprises the separation of minerals from their ores or associated bodies by a flotation process. utilizing a suitable frothing medium together with an improved mineral collecting agent.

In carrying out my invention by the well known flotation process, I employ a suitable 50 frothing agent or frothing aromatic sub- Application filed October :1, 192a. Serial-K0. 818,854.

stances such as cresylic acid, cresote and phenol. The ore is properly pre ared bygrinding, classifying, dilutin an with or without conditioning with ot er modifying agents.

After the ore is made up into a pul suitable for the flotation rocess, and, at a dtsired time, a hydrogenate aromatic sulphur compound is introduced therein. This sulphur compound difiers from the well known thioureas and alkyl thiocarbonates, in that it is formed from the interaction of hydrogenated I phenols, carbon disulphide and a suitable alkali metal hydroxide such as sodium and potassium. Both frothing and collecting properties are possessed by the phenols, and on treatment with sulphur or inorganic sul-, phides these substances act to improve the flotation rocess.

It has een difiicult'to form beneficial flotation reagents by treatin certain phenols with carbon disulphide an sodium hydroxide, for instance, dissolved in water. Hydrogenation of these hydrocarbons in the presence of a catalyst, such as nickel or other suitable substances, at temperatures between 180 and 250 0., produces hydrogen additive compounds. Moreover, by completely hydrogenatigg, for example, cresol, there is produced ethyl cyclohexanol, oH.o.H..,oH.

I ha e discovered that methyl-cyclohexanol reacts readily with carbon disulphide and sodium hydroxide dissolve in water to form what I believe to be sodium methyl-cyclohexanyl xanthate, as indicated below:

The components entering into the reaction to form sodium methyl-cyclohexanyl xanthate are preferably in the following proportion:

This compound is prepared by dissolving 28.5 parts by weight of caustic soda: (96% pure NaOH) in 14.3 partsby weight of distilled water and cooling the solution formed to 25 C. This solution is placed in a suitable receptacle and while shakin the receptacle, or otherwise agitatin the so ution, 35.8 parts by weight of methy -cyclohexanol and 35.9

parts] by weight of carbon disulphide are added all at once. A reaction takes place slowly and the reaction mixture gradually becomes a light straw-yellow color. The mixture should be well agitated and kept fairly cold at all times by any suitable method and means'of cooling.

4 After a sufiicient time, generally not lon er than an hour, the reactionmixture solidi es. Up to the time ofsolidification, there 1s not much rise in the temperature of the reaction mixture, and the temperature does not rise to a dangerous point, even upon prolonged standing without cooling. All the while the reaction is taking place there is a gradual darkening in color and when the reaction is finally completed, the mixture assumes a more or less dark brick red color. V

The crude reaction mixture consists of some sodium carbonate together with sodium thiocarbonate, sodium sulphohydrate and the de-' sired sodium methyl-cyclohexanyl xanthate.

If it is desired to isolate the pure sodium methyl-cyclohexanyl xanthate the crude reaction roduct can be extracted with acetone. After ltering, the acetone solution containing the sodium methyl-cyclohexanyl xanthate can be treated with ether to cause the sodium methyl cyclohexanyl xanthate to precipitate therefrom. v

This new thiocarbonic acid derivative of hydrogenated cresylic acid is soluble in water, alcohol, acetone, etc. It has a water cress odor and seems to decompose when heated to temperatures of from 90 to 110 C, with a darkning in color. It appears that this new compound is formed according to the following reaction equation:

4C.H1BCH,.OH cos. 9NaOH 4cH..c.H..ocssNa M200.

Nagcsg crude reaction product which may be introduced directly into the mineral flotation process without purification, contains approximately of sodium methyl-cyclohexanyl xanthate.

While,- for purposes of illustration, the type xanthate compound has been described with reference to hydro enated cresylic acid (methyl-cyclohexanol I wish it to be clearly understood that the homologues and analogues of.methyl-cyclohexanol can be used to prepare xanthates having properties similar to sodium methyl-c .clohexanyl xanthate. Instead of using cresy ic acid as the basic substance to be hydrogenated and finally converted into a xanthate, phenol may be hydrogenated and employed asdescribed and claimed in application Serial No. 292,607, filed July 13, 1928. Besides phenol, as listed below, any of the following substances can be advantageously utilized:

Phenol o-Xylenol p-Xylenol Cumenol Carvacrol Thymol Eugenol Orcinol Besides being susceptible to variations in the alcohols or alcoholic reacting substances entering into the reaction to form the xanthates, these compounds are also susceptible to variations in the metallic hydroxides entering into the reaction. For example, potassium hydroxide, and hydroxides of the other alkali metals may be employed to produce xanthates having properties very similar to above.

In carrying out the separation of minerals in accordance with my invention, the ore is properly prepared by grinding, classification and dilution, and conditioning with other modifying agents if desired. The ore is then subjected to a flotation process employing a suitable frothing agent or frothing aromatic the sodium compound described in detail substance such as cresylic acid or other similarly reacting substances. After the above preparation, the sodium methyl-cyclohexanyl xanthate or other corresponding compound is introduced into the ore pulp.

The following tabulation illustrates a test run on a sample:

Utah Copper Mill heads, delaying 0.94% Cu.

Ground with 5 lbs. burnt ume' per ton of ore Sodium methyl-cyclohexanyl I xanthate as a collector 0.04 lbs. per T. Cresylic acid, as a frothing agent 0.1 lbs. per T. Copper concentrate 16.54% Cu. Copper tailings l. .05% Cu.

Percentage extraction From the foregoing results, it will be appreelated that thenew mineral collecting agents forming the subject matter of this application, materially and advantageously aflect mineral separation processes in which they are employed. Also, the compounds hereinbefore described may be rather easily prepared from relatively low cost raw materials which,

together with the effectiveness of the compounds, results in low production costs of the mineral products.

These new flotation agents stabilize mineral flotation froth, have selective properties, drop iron from copper ores, are active collectors on zinc ores and are very effective even on coarsely ground ores. The latter is particularly desirable as much time can be saved in the preparation of the ores prior to treatment.

' lhus it will be seen that this invention makes it. possible to more 'efliciently separate minerals from their ores than heretofore accomplished.

While I have herein shown and described a practical and satisfactory process and agent for carrying out my invention, it is, of course, ObVlOllS that various modifications may be made therein without exceeding the scope of my invention, it being understood, for example, that the homologues and analogues of the hydrogenated phenolic bodies may be employed in combination with carbon disulphide and alkali metal hydroxides to produce'flotation collecting agents. 1

I claim: 1. A method of froth flotation for ores and like bodies comprising introducing into a suitably conditioned ore pulp a thiocarbonic acid derivative of a hydrogenated methyl,

.7. In a froth flotation method for concentrating ores and like bodies the step of introducing into ore pulp sodium methyl-cyclohexanyl xanthate.

8. A method for treating an ore comprising grinding the ore into particles, classifying and conditioning the mass by adding a frothlng agent thereto and introducing therein a thiOCilIbOIllC acid derivative of hydrogenated creso 9. In a flotation method for concentrating ores and like bodies, the step of introducing into an ore pulp, an alkali methyl cyclohexanol xanthate.

10. In a froth flotation method for concentrating ores, the step of introducing into an ore pulp, an alkali metal alkyl substituted hydroaromatic alcohol xanthate.

11 In a froth flotation method for concentrating ores, the step of introducing into an ore pulp, an. alkali metal alkyl substituted hydroaromatic monohydroxy alcohol xanthate.

12. In a froth flotation method for concentrating ores, the step of introducing into an ore pulp, an alkali metal poly alkyl substituted hydroaromatic alcohol xanthate.

13. In a froth flotation method for concentrating ores, the step of introducing into an ore pulp, an alkali metal poly substituted hydroaromatic alcohol xanthate.

In testimony whereof I afiix my signature. RHETHERFORD B. MARTIN.

trating ores and like bodies the step of introducing into an-ore pulp a thiocarbonic acid derivative of a; hydrogenated methyl substituted phenol.

. .5. A froth flotation method for concentrating ores and like bodies comprising introducing into ore pulp a thiocarbonic acid derivative of hydrogenated cresol so as to concentrate the value.

6. A method of froth flotation for ores and like bodies comprising introducing into ore pulp an alkali metal salt of a thiocarbonicv acid compound containing a methyl derivative of cyclohexanol so as to concenerate the value. 

